Generally, PC cards, such as memory cards, are data input devices which are electrically connected to personal computer or other electronic apparatus. The data stored in the PC card is transferred to the electronic apparatus. Memory cards are portable instruments which are readily inserted and extracted from a connector mounted in a stationary device which may be used with the PC card for removably coupling the PC card to a printed circuit board in said stationary device, for instance.
One of the problems in manufacturing PC cards as described above involves the build-up of electrical charges in the PC card. Specifically, charges are generated in the PC card during handling since the card generally is a portable instrument often carried on a human body. When a card bearing charges is inserted into an electronic apparatus or the connector thereof, the charges flow to the electronic apparatus through the connecting terminals of the connector. The charges can result in damage to or ultimate failure of the internal integrated circuits or other circuit elements on the card as well as the electronic apparatus itself.
Consequently, structures have been embodied in PC cards and the mating card-receiving connectors for removing static electrical charges stored in the cards. The card typically is grounded to the card-receiving connector. To facilitate grounding and to provide effective static protection, PC cards have been provided with conductive grounding contacts for engaging appropriate grounding elements such as clips or terminals on the card-receiving connector. In fact, with the recent standardization of memory card-receiving connectors, the grounding contacts on the PC card (and the grounding clips of the connector) are provided at fixed locations along the outside edges thereof.
Although some memory card grounding contacts are electrically coupled to conductive trays or plates which, in turn, are connected to the grounding clip of the card-receiving connector, it is electrically more desirable to have as direct a ground connection as possible between the card grounding contact and the ground circuit of the underlying circuit board. Therefore, grounding clips have been developed for the card-receiving connector which include a card-engaging contact portion located on an inside surface of the guide arms of the connector for directly electrically engaging the memory card as it is inserted into mating engagement with the card-receiving connector. The grounding element further includes a board-engaging ground portion for engaging the grounding circuit of the underlying circuit board. Moreover, since fastening devices (such as solder tails, interference fit boardlocks or screws) are used to secure the guide arms of the connector to the underlying circuit board, some grounding clips have been coupled to or incorporated in the fastening devices themselves so that the grounding clip is electrically coupled to the ground circuit of the underlying circuit board (by way of the conductive fastening device), while at the same time securing the guide arms thereto. Screws equipped with nuts have generally been the fastening device most often employed due to their removable nature and reliability.
In the case of stacked or "dual port" card-receiving connectors, the design of the grounding clip becomes more complicated since the upper card-receiving connector must also be electrically coupled to the ground circuit of the underlying board. Some grounding clips have been uniquely designed for dual port card-receiving housings, however these designs necessitate separate dies and separate assembly equipment when the dual portion applications are utilized. Some grounding clips for dual port connectors have been designed for the lower card-receiving connector with an upper ground portion (on an upper surface of the guide arm integral with the card-engaging contact portion of the clip) for electrically engaging the lower ground portion of the upper card-receiving connector. However, the same clip cannot easily be adapted for use on the upper card-receiving connector since the upper ground portion must allow the fastening device to pass therethrough so it does not extend above the upper surface of the guide arms. Accordingly, grounding clips have been uniquely configured for the upper and the lower as well as for the right and the left grounding locations, since the clip is typically asymmetrical. See, for example, the prior art grounding clip shown in FIG. 1.
Therefore, it is logistically and economically desirable to provide a single grounding clip and utilize it in any or all grounding locations of both single and dual port connectors, including top, bottom, left and right grounding locations. Such a universal grounding clip would avoid the added costs associated with changeover die inserts, inventory, and assembly of each separate part. The present invention is directed to providing such a universal grounding clip.